Swapping those speakers would likely be lateral at best. If you are still pleased with the sound of the Kefs how about adding a subwoofer? This will likely be the best bang for the buck. Good luck and cheers.
Speaker upgrade?
Hi. I am running some KEF 104/2 with Morel tweeters. Amplifier is Parasound 2250 running through a Harman Kardon 730. The sound is pretty darn good. Bass though might be a little lacking. I have my eye on some PSB Stratus Golds in excellent condition. Speakers look like new but unable to listen to them. Would I be basically going sideways and not gaining much except for lower bass response in the Golds? Price is $650. Thanks in advance for your response. John